"angularfire2@5.0.0-rc.4 requires a peer of ... but none is installed" error, tried modifying package.json with angular/core@^5.5.0 but no matching version found

Firebase: ^4.5.0

AngularFire: ^5.0.0-rc.4

I’m gonna explain straight the problem 'cause it is a bit complicated with the pattern … I’ve cloned an Ionic project from github, then run ionic serve and installed the missing modules. The problem came up with the installation of angulafire2, using npm npm install angularfire2 . It tells me this:

and if I run ionic serve the error page comes up saying that it can’t find the module @firebase/app even if it was installed. So I’ve tried following what the warning told me, and changed the versions of angular/common, angular/core etc to ^5.0.0 as requested by angularfire2, then run npm install, but an error shows up:

I’m really stuck into this problem and can’t go on, how do I resolve this?

[davideast]

Right. Don’t use ^5.5.0, use ^5.0.0.

[awsaunier]

This is no longer a problem for me. The npm instructions gave me errors but I installed it a different way with npm and then there were no errors.